Journal or Book Title
Transactions of the ASAE
Field experiments were conducted for three years (1989-91) at the research farms of Iowa State University near Ames and Ankeny to evaluate water-table management (WTM) effects on groundwater quality. Water-table depths of 0.3, 0.6, and 0.9 m were maintained in field lysimeters at the Ames site, and variable water-table depths were maintained in a subirrigation field at the Ankeny site. Water samples were collected from various soil depths to analyze NO3-N concentrations in groundwater. Concentration of NO3-N in groundwater changed with WTM practices. The lowest NO3-N concentrations were observed under the shallow water-table depths. NO3-N concentrations in groundwater generally decreased with increased depths and time during the growing season under all WTM practices. Crop yields were higher under water-table depths of 0.6 to 0.9 m than under other water-table depths, and corn yields decreased under shallow water-table depths of 0.2 to 0.3 m. Results of this study indicate that WTM practices can be used to substantially reduce the concentrations of NO3-N in groundwater. Results also strongly support the need for further research with WTM practices for water quality and crop production.
American Society of Agricultural and Biological Engineers
Kalita, Prasanta K. and Kanwar, Rameshwar S., "Effect of Water-table Management Practices on the Transport of Nitrate-N to Shallow Groundwater" (1993). Agricultural and Biosystems Engineering Publications. 500.